Temperature Goldilocks: A Comparison of Static Storage Options in Pediatric Heart Transplantation.

BACKGROUND: Static storage at 4 - 8°C has demonstrated improved outcomes in both adult and pediatric heart transplantation (HT). Recently, 10°C static storage emerged as a cheaper alternative that improves outcomes in adult HT relative to ice. This study compares pediatric HT outcomes with static storage on ice, at 4 - 8°C, and 10°C. METHODS: This was a single center retrospective study of pediatric HTs from 5/2022-7/2025. Only donation after brain death HTs were included. The organ preservation systems used vary between static storage on ice, at 4 - 8°C, and at 10°C. Outcomes included post-transplant clinical course, follow up data, and mortality data. RESULTS: In total, 51 transplants met inclusion criteria, of which 18 (35.3%) used ice storage, 17 (33.3%) used 4°C storage, and 16 (31.4%) used 10°C storage. Recipient baseline demographics, were similar between the groups. Rates of intraoperative right ventricular dysfunction were higher in the ice group (66.7% ice vs 23.5% 4°C vs 18.8% 10°C, p=0.007). Postoperatively, rates of primary graft dysfunction were similar between the groups. Vasoactive inotrope scores (VIS) were different immediately post-HT (8.5 ice vs 7.0 4°C vs 2.5 10°C, p<0.001) with significant differences across all pairwise comparisons. VIS were also different at 24 hours post-HT (7.0 ice vs 5.0 4°C vs 2.5 10°C, p<0.001), with significant pairwise comparisons between ice vs 10°C. Mortality at 30-day, and 1-year were comparable between the groups. CONCLUSIONS: This initial experience demonstrates promising early outcomes utilizing the 10°C cooler for cardiac allograft preservation in the pediatric setting.